Sound-box mounting.



W. T. LAKIN.

souwn B'OX MOUNTING. APPLICATION FILED JAN. 8. I9\8.

Patented Apr. 22, 1919 2 SHEETSSHEET I- lf/VE/VTOR W/LLM/v 77 LAM/y,

WITNESSES AJTO/WEYS W. T. LAKIN.

SOUND BOX MOUNTING. APPLICATION FILED JAN. a. 1918.

2 SHEETSSHEE,T Z.

" IUTOR/l/EVS W/LLM/W". L A m/y,

Patented Apr. 22, 1919.

WITNESSES mmgsso WILLIAM T. LAKIN, F LOIQG MARYLAND.

SOUND-BOX MOUNTING.

Specification of Letters Patent.

Patented Apr. 22, 191%.

Application filed January 8, 1918. Serial No. 210,873.

To all whom it may concern:

Be it known, that 1, WILLIAM TROUPE LAKIN, a citizen of the United States, and a resident of Long, Allegany county, Maryland, have invented a new and useful Improvement in Sound-Box Mountings, of which the following, is a specification. My invention relates to in'iprovements in phonographic tone arms, and it consists in the constructions, combinations, and arrangements herein described and claimed.

An object of my invention is to provide a tone arm including as one of the essential features a conduit, so mounted upon the end of the tone arm as to be capable of being swung completely back out of the way, making the turn table accessible for the placing and removing of the records.

Another object of the invention is to provide a tone arm, including a reproducer neck, adjustably mounted upon the end of the sound conduit, making the reproducer adaptable to both vertically cut and laterally cut records.

Another object of the invention resides in the manner of pivotally supporting the tone arm and of affording also a continuous unbroken tone passage.

Other objects and advantages will appear in the following specification, reference being had to the accompanying drawings in which:

Figure 1, is a plan view of the tone arm.

Fig. 2, is a detail cross section of the sound conduit mounting on the tone arm.

Fig. 3, is a detail section of a portion of the mounting.

Fig. 4-, is a detail section of the coupling connecting the reproducer to the reproducer neck.

Figs. 5 and 6 are face views of the opposing portions of the sound conduit mounting.

Fig. 7, is aside elevation of the" parts shown in Fig. 1, portions being shown in sections.

a Figs. 8 and 9 are detail views of a poiition of the reproducer neck, and

Figs. 10 to 12 inclusive, are detail views of several modifications of bearing pins hereinafter described.

in my invention I provide the swinging tone arm 1, which swings horizontally over the top of cabinet 2. The large end of the tone arm 1 has a pivotal mounting on the end of the fixed tone arm 3 which is con {sealed in the cabinet 2 and terminates in a horn or some other sound amplifying device. The tone arm 3 usually'connects with a wood horn which terminates at a latticed front of the cabinet, but this feature having no connection with the invention need not be dwelt upon here.

Upon the end of the swinging tone arm 1, is a sound conduit 4 which, together with the reproducer neck 5 carried thereby, forms a substantially $-shaped end member. The sound conduit 4 is capable of being turned through an arc of approximately 180. The ability to turn the sound conduit back into the dotted line position indicated in Fig. 7, facilitates the placing and removal of records on and from the turn table 6. A. reproduccr 7 is carried by the reproducer neck 5, and is mounted on the neck by means of,'a novel pivotal coupling illustrated more clearly in Fig. 4.

The pivotal mounting of the sound conduit 4 on the tone arm 1, consists of a pair of plates formed by flaring the ends of the respective members, and securing the flared plates together as will presently appear. A plate 8 is formed integrally on the end of the sound conduit 1, and the periphery of the plate 8 may be slightly curved at 9 in order that it may be encompassed by the curved periphery 10 of the plate 11, also integral-1y fori'ned on the end of the tone arm 1. Ohviously the plates 8 and 11 may be made separate members and secured upon the respective ends of the sound conduit 4 on the tone arm 1. It is preferable however. to flare or expand the ends of these members into the shape of the plates, thereby providing unitary structures.

A considerable space between the opposing surfaces of the plates 8 and 11 isshown in Fig. 2. In actual practice these plates will'be so formed as to come very close together, consequently materially reducing the thickness of the coupling between the sound conduit and the tone arm. Ball bearings 12 are disposed between the plates. The plate 8 has a ball race 13 in which the balls run, and the plate 11 has a cone 14 which engages the balls. 1

The cone 14 includes an extension which fits into the adjacent point of the throat of the sound conduit to prevent the escape of sound. Attention is directed to Fig. 3. Here it will be seen that a throat 15 projects into the flared mouth 16 at the end of the sound conduit +1. It will also be obsessed that the outer surface of the throat 15 is tapered so as to closely fit the-flared mouth 16. It will be readily understood that the throat and the surface of the mouth will be very close together, and so it can be readily understood, that the escape of sound around the joint between the two members, will effectually be prevented. As an incidental feature of construction, the throat 15 and the flared end 16 of the sound conduit are so fitted together that the bore of the one forms a substantial continuation of the bore of the other. Instead of forming the cone 1 1 and the ball race 13 on the tone arm and sound conduit respectively, the location of these parts may be reversed, and may also be so modified in construction to conform to any particular requirements and still retain the essential features just described and illustrated in the drawing.

Stud pins 17 and 18, upon which lock nuts 19 and 20 are threaded hold the plates 8 and 11 together. The base of each of the pins is fixed in one of the plates. Attention,

is directed to Fig. 2. Here it will be seen that the stud pin 18 is threaded on the extremity while the base of the pin is smooth and fixed in the plate 11. The pin 18 projects through a slot 21 in the plate 8. Similarly, the stud pin 17 fits in the plate 8 and projects through a slot 22 in the plate 11.

These slots are arcuate as shown in Figs. 5 and (i .and are disposed concentrically to the tone arm and sound conduit at the point of connection of these members. The arouate formation of the slots 21 and 22 is shown in Figs, and '6. It will therefore be observed that the respective pins 17 ,and 18 stand on the base of each of the slots. In fitting the plates 8 and 11 together, the pins are made to project through the companion slot of each of the plates, whereupon the plates are secured together by means of the lock nuts as will presently more fully appear. The pins 17 and 18 are also adapted to abut the other end of each of the other slots in which the respective pins play, and

thus limit the backward and forward motion of the sound conduit.

'VVashers 23 are screwed upon the threaded ends of the respective pins and precede the lock nuts 19 .and 20. The washers 23 are screwed only far enough down on the pins to secure freedom of rotational movement of the sound conduit on the tone arm, and are so adjusted on the pins that lateral motion on the tone arm 1 is prevented. The lock nuts 19 and 20 then follow, and are screwed tightly against the washers. It will 'be observed that the edge of the plate 11 is curled or curved more than is the edge 19 of the plate 8. The edge of the curved portion of the plate 11 is slightly restricted so that it may snap over the edge of the plate 8 and form a tight joint between the openings aaoaaae plates. This arrangement is clearly illustrated in Fig. 2. Here it will also be seen that the outer surface of the curved edge 10 is knurled principally to give the con pling a more pleasing appearance.

The reproducer neck 5 is radiallyadjust able upon the end of the sound conduit 1,

by the means illustrated in Figs. 8 and 9. A set screw 2-1 is screwed into the open end of the sound conduit 1 at one side. The elbow of the reproducer neck 5 has an an nular groove 25 adjacent to the end thereof, with an inlet 26- which permits the introduction of the end of the set screw 21 into the groove 25 by unscrewing the screw 21until the end of. the screw comes flush with the bore of the sound conduit. A plurality of 27 are formed in the groove These openings are smooth, and when the desired adjustment of the reproducer neck size is obtained, the set screw 2-1 is simply turned into engagement with the proper one of the openings 27, whereupon the adjustment is held as clearly illustrated in Figs. 1 and 9.

The reproducer neck 5 may be disposed in either the right or left hand positions indicated in Fig. 1 or in the central position with the diaphragm of the reproducer downward and parallel to the turntable. The adjustments in the first two instances indicated A and B are where the reproduce].- is employed on laterally undulating records, and the adjustment in the second instance 0 is where the reproducer is employed on perpendicularly cut records. The intermediate holes or openings 27 simply provide an additional range of adjustment and may be employed as needed or discarded altogether.

The compression coupling between the reproducer 7 and the 'reproducer neck 5, previously. mentioned, includes a plurality of rubber gaskets concealed in a cup 29, and encircling the free end of the reproducer neck 5 as clearly shown in Fig. 1. The free end of the neck is split at 30. The gaskets 28 are compressed by means of the compression screws 31 which pass through the gaskets and are threaded into the back of the reproducer 7. The edge of the cup 29 is slightly spaced from the back plate of the reproducer in order to give the screws 31 a certain amount of movement wherein the rubber gaskets 28 are compressed and consequently expanded against the free end of the neck 5. This compression coupling not only serves to holdthe reproducer firmly in position on the end of the neck, but also permits the radial adjustment of the rcproducer on the end of the neck, since the reproducer may be readily turned on exerting a little pressure to overcome the friction. between the expanded gaskets on the end of the neck.

Another important feature of the invenaeor neu swinging tone arm 1 on the tone arm 3. Attention is directed to Fig. 7. A standard is mounted on a bracket 33, directly in the I center of the vertical portion of the elbow. The standard has a reduced portion at the top providing a shoulder 34: upon which the bridpe 35' of the tone arm 1 rests. The

standard is centrally threaded to receive the threaded reduced end of a stabilizing pin 35. The pin 35 tapers slightly. The pin has cone bearing 36 near the top, which termi natcs in a threaded shank 37 surmounted by head 38. T'hecone bearing 36 engages a conical recess 39 in the top wall of the tone arm. The threaded shank 37 screws into a threaded opening in the horizontal portion of an arm 40. The arm l0 is-an extension of the bracket 33'on which the standard 32 is mounted. The bracket 33 is introduced into the channel of the tone arm through an opening t1, the adjacent portion of the bracket 33 being wrapped with rubber 42 in order to prevent any rattling that might ensue by the contactof the metallic portion of the bracket and the tone arm. The bracket and the arm 4(O are secured in place on the stationary tone arm 8 by the screws illustrated, or'by some other suitable means.

G ycerin, Vaseline, or some other suitable sealing material is placed in an annular channel 43 formed on the upper edge of the tone arm 3, which receives the end of the tone arm 1. It will be understood that the of the elbow of the tone arm 1, runs in the channel and the sealing material which fills the remainder of the channel, prevents the escape of sound around the'joint between the two members or" the tone arm. its stated above, this sealing material may consist of any suitable substance, such for instance as 'rlycerin, Vaseline, etc.

An iris diaphragm is located in the stationary tone arm 3, but more properly, at the uinion of the stationary tone arm and the amplifying horn within the cabinet. The diaphragm has a lever 45 projecting out one side, and by means of which the diaphragm may be opened or closed to regulate the volume of sound passing into the stationary ain'iplifying horn or trumpet.

The operation of the device will bereadily understood from the foregoing description when taken in connection with the -folassembling the swinging tone arm 1 on the stationary tone arm will be readily understood. Itshouldbe observed that the distance between the uppern'lost portion of the tone arm 1 and the under surface of the horizontal portion of the arm %0 is the same as the distance between the shoulder 34: and the upper surface of the reduced portion of the standard 32, The reason for this arrangement will readily be seen. The elbow of the tone arm 1 is inserted over the end ofthe standard until the bridge 35 rests on the shoulder 34. in order to be able to do this, the respective distances just described must be the same in order to enable the placing of the elbow beneath the horizontal por-. tion of the arm 40.

The tone arm having been put in place, is held in position until the stabilizing pin 35 is screwed in place, whereupon the tone arm I is supported by the cone bearings 36 and 39 at the top and the shoulder 34 oi the standard 32, at the bottom. The diameters of the various portions of the stabilizing pin 35, decrease from the head 38 to the pit of the pin. This structural feature of the pin of course permits the insertion of the pin through the opening in the arm 20 until the threaded extremity of the pin is screwed into the standard 32. The shoulder adjacent to the threaded extremity of the pin eventually binds against the top surface of the standard, and the cone bearing 36 will be found to be in proper position in the conical opening 39 in the tone arm, so

that a mounting for the tone arm is pro- VlClBCl'Wll lCll holds the tone arm securely in position and at the same time prevents rattling and lateral mot-ion of the tone arm on the stabilizing pin.

I The pivotal coupling of the sound conduit 4 on the tone arm 1., is of such a nature that the sound conduit may be swung back through approximately an arc of 180 to get the reproduce! out of the way and permit the ready placing or removal of a record on and from the turn table. This feature is one of the most important of the whole invention. The manner of forming the piv otal coupling is thought to be fully understood. Briefly, however, consists of the pins 17 and 18 fixed on the respective plates 8 and 11, which project throu fh a companion arcuate slot 21 and 22 in the respective plates. Nashi-ers 23 are screwed upon the threaded ends of the pins until the ball bearings 12 in the ball race 13 and pressed on tightly enough to prevent rattling and still secure easy movement of the sound conduit on the tone arm. The lock nuts 19 and 20 are then screwed into position, wheredpon the coupling" is ready for use. Althoiigh it matters little in which location the respective stud pins are mounted on the respective plates, it should be observed that tone arm 1, and the lock nut 20 is tightly inclosed in the crook of the sound conduit '4, these nuts are out of the way as it were and the possibility of striking there against is materially reduced.

The construction of the compressed coupling and the manner of securing the radial adjustment of the reproducer neck 5 on the sound conduit 4, are features which are thought to be understobd. The compression coupling consists of a plurality of rubber gaskets which are compressed against the end of the reproducer neck, by screwing down the compression screw 31. The slight space between the edge of the cup 29 which houses the rubber gaskets, and the adjacent surface of the back plate of the reproducer, permits the screws to be moved through this distance and the gaskets to be compressed accordingly.

The back of the reproducer 7 is preferably provided with an annular flange into which the edge of the cup29 fits, as shown in Fig. 4.

Figs. 10 to 12 inclusive illustrate certain modifications of more or less flexible bearing pins to be used in connection with the reproducer 7. These bearing pins have for their object, the holding of the needle bar 54; in place. These pins are supported in brackets and are so arranged that by their resiliency, a freer rocking motion of the needle bar is obtained. Fig. 10 illustrates a pin composed of two parts 46 and 47.. The part 46 has a right hand thread and is extended at 48 and has a left hand thread. The extension &8 screws into a threaded socket 49. The portion 47 is cut away or flattened at 50 so that the bearing pins may be more resilient. The pins in Figs. 11 and 12 are also reduced in the middle. The one vshown in Fig. 11 is similar in appearance to the portion 47, with the exception that the head 51 is threaded. The central portion of the pin in Fig. 12 is cylindrically constricted at 52, this constriction also being for the purpose of giving the stylus bar added resiliency and increasing its sensitiveness.

While the construction and arrangement ing in an integral coupling member, a sound panying drawings is that of a generally preferred form, obviously modifications and changes may be made without departing from the spirit of the invention or the scope of the claims.

I claim,

1. A tone arm having a bent e d terminating in an integral coupling mem er, asound conduit having a cooperating coupling member at one end applied to said tone arm coupling member and being curved to place the axis of the cp'eriend of the sound conduit at between the plates,

neonate;

right angles to the axis of the end oi the coupling, a reproducer neck radially adjustable in said 0 en end and in a plane parallel to the axis ot the coupling, and a radially adjust-able reproducer mounted on the end of said neck.

2. A tone arm comprising a sound conduit havin a set screw, and a reproducer neck inclu ing an elbow, having an annular slot with an entrance opening directed toward the opening of the elbow to admit the point of the set screw into the slot in assembling the parts, and a plurality of unthreaded apertures in the bottom of the slot for receivmg the point of the set screw when the set screw is screwed in place.

3. A tone arm having one end flared to form a plate, a sound conduit having one end flared to form a cooperating plate, the edges of the plates being shaped to snap together, bearing means mounted between the plates, means carried by each plate engaging in the companion plate to limit the rotational movement of the sound conduit on the tone arm, adjusting means carried by said engaging means to regulate the pressure on said bearings, and locking means on said engaging means for binding on said adjusting means.

4. A tone arm having one end flared to form a plate with a slot, a sound conduit having one end flared to form a companion plate with a slot, the edges of said plates being shaped to snap one upon the other pins carried by the plates engaging in the companion slots, bearing devices mounted a washer threaded upon each pinto adjust the pressure on said bearings, and lock nuts following said washers and said pins.

5. A tone arm having a flared end to form a plate having an arcuate slot, having a flared end providing a companion end having an arcu'ate slot, the edges of said plate being curved and arranged to snap one in the other, a ball race formed on the sound conduit, a bearing cone formed on'the tone arm, bearings disposed between said cone and said race, a portion of the cone eXtending into the adjacent portion of the sound a coupling plate, bearing means located between .the plates, and means holding the plates together including lock nuts located in the res ectivecrooks, said lock nuts being thus shielded.

. 7. A tonearm, a reproducer neck having a split end, a reproducer mounted-ion the neck, a cup having the edge normally spaced from the back plate of the reproducer, compressible means located in the cup engaging the split end of said neck, and means pass ing through the cup and said compressible means into said back plate, for compressing said cempressible means and expanding it against said neck.

8; A reproducer mounting including coupling plates each carrying interengageable portions arranged to snap together in assemhling the coupling, bearing means located between said coupling plates and keeping the plates spaced apart, and means carried by each of the plates and extending through the companion plate enabling the regulation of the pressure of the plates 011 said bearing means.

WILLIAM T. LAKIN Witnesses:

JOHN E. ZILCH, J OHN SCHILLER. 

